So I went ahead and purchased the Modtronix SBC65EC. Here it is with power and Ethernet:
It took a while for me to install all the Microchip development software, but finally it was working and I compiled the Web server for the chip:
So with the stock Web server working, I decided I'd start to work on having the board initiate communications. First I started with a static IP for the board. TCP transmission worked fine. UDP transmission was less promising. It ARPed the destination MAC, but then didn't put the MAC in the Ethernet header of transmitted UDP packets!!!
Well, at least I have the source code and if motivated I can find the bug myself, fix it, and recompile. It also isn't clear to me how/if DHCP works on the board.
Suffice it to say, I'm sick of these almost-IP capable microcontroller boards!
To cheer myself up, I picked up a 9.6V car for Sycophant II: